Catalyst and process for polymerizing alpha-olefins utilizing titanium halide derivatives



United States Patent 13 Claims. (Cl. 260-93.7)

This invention relates to novel derivatives of titanium halides. Moreparticularly, it relates to the reaction products of titanium halideswith organic electron donors, these reaction products upon properactivation being active catalysts for the low pressure polymerization ofalpha olefins.

This application is a division of patent application Serial No. 777,828filed December 3, 1958, now US. Patent 3,069,446.

The low pressure polymerization and copolymerization of alpha olefinsand diolefins with catalyst systems made up of a partially reduced,heavy, transition metal halide and a reducing metal-containing compound,to high density, often isotactic, high molecular weight, solid,relatively linear products has been assuming ever increasing importanceand is now well known.

The alpha olefinic feeds utilized in polymerization and copolymerizationinclude ethylene, propylene, butene- 1,'heptene-1, dodecene-l, etc.,with ethylene and propylene preferred.

Among the diolefins that can be used in copolymerization are butadiene,isoprene, piperylene, vinylcyclohexene, cyclopentadiene, 1,4-pentadiene,etc. It is to be understood that wherever the term polymer is usedherein, it connotes both homoand copolymers.

The low pressure process is described in the literature, e.g., seeBelgian Patent 538,782 and Scientific American, September 1957, pages 98et seq.

It has now been found that novel derivatives of titanium halides areuseful for this type of polymerization. These novel derivatives are thereaction products of titanium halides with organic electron donors asexplained in further detail below. The reaction products on properactivation are useful in the low pressure polymerization of alphaolefins. Alone or activated, they are possessed of catalytic activityfor isomerization, reduction, oxidation, etc.

The titanium halides utilized in the preparation of the reactionproducts can be titanium chlorides, bromides or iodides with the firsttwo preferred, having a minimum of two halogen atoms, e.g., TiCl TiClTiBr TiBr and TiCl These materials are reacted with organic electrondonors.

Particularly preferred electron donors are triphenylchloromethane,diphenyl-chloromethane, benzyl sulfide, phenyl urethane, andtetraethyl-ammonium bromide.

An electron donor suitable for the needs of this invention may be of twotypes.

(1) A compound capable of donating a pair of elec-' trons to thetitanium halide resulting in a complex which contains a cation of markedstability.

(2) A compound capable of donating an anion to the titanium halidethereby producing a cation of high stability.

3,103,545 Patented July 6, 1965 ice 2 min 2TiX4 niN rixfi The exactstructure-of the reaction product is very difficult to postulatebeoauseof the complicated nature of the molecule. Because of that, itshould be understood that where stoichiometric formulae are shown, theyare based on halogen analysis and are not intended to connote the actualmolecular arrangement. In general, the molecular ratio of titaniumhalide to organic electron donor is in the range of 1 to 1 to 4 to 1.

The titanium complexes are prepared by mixing the two components in aninert hydrocarbon diluent. In individual preparations one or both of thereactants may be partly or completely soluble in the diluent, e.g., TiClCCl, CH S, CHCL TiBr In each case, the procedure involves stirring thereaction mixture (at atmosphere pressure) in an inert atmosphere (N forone to'several hours and at a temperature between about 25 C. and theboiling point of the diluent. The resulting slurry is then filtered andthe solid product washed with several portions of heptane. The complexis dried by vacuum at room temperature. Typical reaction conditions arecited in Table 1. All the products are colored (red to green) solids,decomposed by air or moisture, but stable in a nitrogen atmosphere.

The resulting reaction products are activated with a metal alkylcompound, i.e., a trialkyl derivative of aluminum, gallium, and indium,e.g., aluminum triethyl. The two components in the proper proportionsare admixed in an inert solvent, e.g., a -C to C parafiin such asisopentane or n-heptane, or an aromatic such as benzene or xylene, attemperatures between 0 and 150 C. Slurries of dark colored reductionproducts are obtained with some solubility in the diluent. Thesolubility of the resulting products depends on the nature of thetitanium complex. The TiCl .CH -S-CH complex reacts with AlE=t to yieldproducts that are nearly completely soluble in n-heptane.

In general, the preferred ratio of alkyl compound to the titanium halidereaction product is in the range of lto 1 to 10to 1.

In the polymerization, the monomers are contacted with the resultingcatalyst in the presence of the same or differing inert hydrocarbonsolvent such as isopentane, nheptane, Xylene, etc. The polymerization isconveniently effected at temperatures of about 0 to C. and pressuresranging from about 0 to 500 p.s.i.g., usually 0 to 100 p.s.i.g. Thecatalyst concentration in the polymerization zone is preferably in therange of about 0.03 to 0.5 wt. percent based on total liquid and thepolymer product concentration in the polymerization zone is preferablykept between about 5 to 15 wt. percent based on total contents so as toallow easy handling of the polymerized mixture. The proper polymerconcentration can be obtained by having enough of the inert diluentpresent or by stopping the polymerization short of 100% conversion ofthe mono.- mers. When the desired degree of polymerization has beenreached, a C to C alkanol such as methyl alcohol, isopropyl alcohol orn-butyl alcohol, desirably in combination with a chelating agent forpolymer deashing such as acetylacetone is normally added to the reactionmixture for the purpose of dissolving and deactivating the catalyst andfor precipitating the polymer product from solution. After filtration,the solid polymer may be further washed with water, alcohol or acid suchas hydrochloric acid, dried, compacted and packaged.

The polymers produced have molecular weights in the range of about150,000 to 300,000 or even as high as 3,000,000 as determined by theintrinsic viscosity method using the 1. Harris Correlation (J. PolymerScience, 8, 361, 1952). The polymers can have a high degree ofcrystallinity and a low solubility in n-heptane. I

It is to be understood that the term low pressure polymer as used hereinconnotes material prepared in V the indicated manner.

The advantages of this invention will be better understood by referenceto the following examples:

EXAMPLE 1 The advantages of this invention will be apparent to thoseskilled in the art. Novel materials are made available which can havegreat importance in catalytic operations.

Since the reaction between TiCl and trityl chloride is nearlyquant-ative and give an intensely colored product (yellow) it followsthat trityl chloride can serve as either a quantitative or qualitativeanalytical reagent for the detection of TiX It is to be understod thatthis inventionis not limited to the'spe cific examples which have beenoffered merely as illustrations and that modifications may be madewithout departing from the spirit of the invention.

What is'claimed is:

1. A catalytic mixture comprising the reaction product of a titanium'hali de having a minimum of 2 halogen atoms and an organic electrondonor selected from the group consisting of triphenyl chloromethane,diphenyl chloromethane, benzyl sulfide and, phenyl urethane, andtetraethyl ammonium bromide wherein said reaction product has beenformed by stirring a mixture of said titanium Metal halide OrganicComponent Conditions 1 Yield, g. Stoiehiometry 2 g. T1014. Room temp,hrs 31.0 GUI-(T1014); 25 E5. TiCl3 75 0., 40 hrs 42. 0 3OOl-(T}Ola)g 25g. TiOlz 75 0., 40 hours 28. 8 3ccl-('D1C12 )4 25 g. 'liOh Room temp.,90111-5. 11. 5 (r/JzGI'IODg-TICLA 25 g. 'IiCl4 1 Room temp, 40 hrs. 24.0 (4 OH2)2S-T1Cl V 25 g. T101 9.5 g. NHCO Et Room temp., hrs. 19. 8rbNHCOzEt-TiCh 25 g. TiBr4 7.5 g. Et NBr 7 Room temp., 90 hrs. 19. 0EtlNBr-TlBrl 1 Reaetants diluted with 200 ml. normal heptane. ZIndicated byhalogen analysis.

3 Triphenyl-chloromethane.

4 Diphenyl-chloromethane.

6 Phenyl methane.

7 'Ietraethyl-ammonium bromide.

The relative activities of the catalyst system (based weight of solidpolymer) were: 7

It should be noted from this table that Ticl -aluminum triethyl aloneonly gave traces of polymer. On the other hand, the use .of the tritylchloride reaction product of TiCl gave an active catalyst.

EXAMPLE u A similar example was run as in Example I except thatpropylene was polymerized. Again the complexed TiCl system activatedwith aluminum triethyl gave a much more active catalyst than TiCl aloneso activated. 'The results and conditions are'shown in Table 3 below.The compound designations are again the stoichiometric ones as explainedpreviously.

halide and said electron donor in an inert hydrocarbon diluent in theabsence of a reducing compound, under an inert atmosphere for one toseveral hours at a tempera ture between about 25 C. and the boilingpoint of said diluent, recovering, washing, and drying said complex, themolecular ratio of titanium halide to organic electron donor being inthe range of 1:1 to 4: 1, and a trialkyl compound of a metal selectedfrom the group consisting of aluminum, gallium and indium, the molecularratio of trialkyl compound to titanium halide reaction product being inthe range of 1:1 to 10: 1.

2. The catalytic mixture of claim 1 in which the titanium halide is TiClthe organic electron donor is triphenyl chloromethane, and the trialkylcompound is aluminum triethyl. V

3. The catalytic mixture of claim 1 in which the titanium halide is TiClthe organic electron donor is triphenyl chloromethane, and the trialkylcompound is aluminum triethyl.

4. The catalytic mixture of claim 1 in which the titanium halide is TiClthe organic'electron donor is triphenyl chloromethane, and the trialkylcompound is aluminumtriethyl. j p

5. The catalytic mixture of claim 1 in which the titanium halideis TiC1the organic electron donor is diphenyl chloromethane, and the .trialkylcompound is aluminum trie-thyl.

Tabl e 3.-Pr0pylene polymerization in 300 ml. rocking bomb at 80 C. for2 hours Complex aCCl-(TiCia)a CCl-(Ti0h)4 T1011 (@GHClh-TlClNHCOlEt-TiC1 g 0. 0. 59 0.59 0.75 0.75 0. 4s 0. 0.57 0.71 0.36 Metalalkyl- AlEta GaEta InEt; AlEts AlEt; AlEt AiEtz AlEta AlEt AlEt; t., g0. 0. 79 1.01 0.57 0.57 0. 57 V 0.57 0.57 1.14 0.57 Propylene, g. 150 7575 75 75 75 75 75 75 Wt. percent- 47 64 '64 69 69 64 69 64 69 DilueutXylene Xylene Xylene Xylene n-Heptane n-Heptane Xylene n-Heptane Xylenen Heptane Metal alkyl/Ti ratio 2. 2. 5 1. 25 1. 25 1O 3 3 5 5 0.23 0.50.5 0. 64 0.69 0. 44 0. 48 0.52 0. 0.33 120 29 23 49 53 19 20 36 1 4 9121 14 38 40 V 18 18 32 '0. 5 4 a 80 39 31 71 25 27 48 1 5 6. Thecatalytic mixture of claim 1 in which the titanium halide is TiCl theorganic electron donor is phenyl urethane, and the trialkyl compound isaluminum triethyl.

7. The catalytic mixture of claim 1 in which the titanium halide is TiBrthe organic electron donor is tetraethyl ammonum bromide, and thetrialkyl compound is aluminum triethyl.

8-. A process for polymerizing an alpha olefin which comprisespolymerizing the alpha olefin in the presence of a catalyst comprisingthe reaction product of a titanium halide having a minimum of 2 halogenatoms and an organic electron donor selected from the group consistingof triphenyl chloromethane, tetraethyl ammonium bromide, diphenylchloromethane, benzyl sulfide, and phenyl urethane, wherein saidreaction product has been formed by stirring a mixture of said titaniumhalide and said electron donor in an inert hydrocarbon diluent in theabsence of a reducing compound, under an inert atmosphere for one toseveral hours at a temperature between about 25 C. and the boiling pointof said diluent, recovering, washing and drying said complex, themolecular ratio of titanium halide to organic electron donor being inthe range of 1:1 to 4:1, and activated with a trialkyl compound of ametal selected from the group consisting of aluminum, gallium andindium, the molecular ratio of trialkyl compound to titanium halidereaction product being in the range of 1:1 to 1.

9. The process of claim 8 in which the alpha olefin is ethylene and thealuminum trialkyl is aluminum triethyl.

10. The process of claim 8 in which the alpha olefin is propylene andthe aluminum trialkyl is aluminum triethyl.

11. The catalytic mixture of claim 1 in which the titanium halide isTiCL; and the organic electron donor is diphenyl chloromethane.

12. The catalytic mixture of claim 1 in which the titanium halide isTiCL; and the organic electron donor is benzyl sulfide.

13. The catalytic mixture of claim 1 in which the titanium halide isTiCl and the organic electron donor is tetraethyl ammonium bromide.

14. The process of claim 8 wherein said electron donor is triphenylchloromethane.

15. The process of claim 8 wherein said electron donor is diphenylchloromethane.

16. The process of claim 8 wherein said electron donor is benzylsulfide.

17. The process of claim 8 wherein said electron donor is phenylurethane.

.18. The process of claim 8 wherein said electron donor is tetraethylammonium bromide.

References Cited by the Examiner UNITED STATES PATENTS 2,843 ,5 77 7/5'8 Friedlander 260-94.9 2,886,561 5/59 Reynolds 26094.9 2,910,461 10/59Nowlin 260-949 2,912,424 1 1/59 Cash 260--94.9 2,932,633 4/ Juveland260-949 2,970,992 2/ 61 Geiser 26094.9

JOSEPH L. SCHOFER, Primary Examiner.

8. A PROCESS FOR POLYMERIZING AN ALPHA OLEFIN WHICH COMPRISESPOLYMERIZING THE ALPHA OLEFIN IN THE PRESENCE OF A CATALYST COMPRISINGTHE REACTION PRODUCT OF A TITANIUM HALIDE HAVING A MINIMUM OF 2 HALOGENATOMS AND AN ORGANIC ELECTRON DONOR SELECTED FROM THE GROUP CONSISTINGOF TRIPHENYL CHLOROMETHANE, TETRAETHYL AMMONIUM BROMIDE, DIPHENYLCHLOROMETHANE, BENZYL SULFIDE, AND PHENYL URETHANE, WHEREIN SAIDREACTION PRODUCT HAS BEEN FORMED BY STIRRING A MIXTURE OF SAID TITANIUMHALIDE AND SAID ELECTRON DONOR IN AN INERT HYDROCARBON DILUENT IN THEABSENCE OF A REDUCING COMPOUND, UNDER AN INERT ATMOSPHERE FOR ONE TOSEVERAL HOURS AT A TEMPERATURE BETWEEN ABOUT 25*C. AND THE BOILING POINTOF SAID DILUENT, RECOVERING, WASHING AND DRYING SAID COMPLEX, THEMOLECULAR RATIO OF TITANIUM HALIDE TO ORGANIC ELECTRON DONOR BEING INTHE RANGE OF 1:1 TO 4:1, AND ACTIVATED WITH A TRIALKYL COMPOUND OF AMETAL SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, GALLIUM ANDINDIUM, THE MOLECULAR RATIO OF TRIALKYL COMPOUND TO TITANIUM HALIDEREACTION PRODUCT BEING IN THE RANGE OF 1:1 TO 10:1.